Some standard content:
Chemical Industry Standard of the People's Republic of China
Industrial Magnesium Oxide
Subject Content and Scope of Application
HG/T 2573-94
This standard specifies the technical requirements, test methods, inspection rules, as well as marking, packaging, transportation and storage of industrial magnesium oxide. This standard applies to magnesium oxide obtained by calcining basic magnesium carbonate and magnesium hydroxide. This product is mainly used in industries such as plastics, rubber, wires and cables, dyes, greases, glass and ceramics. Molecular formula: MgO
Relative molecular mass: 40.30 (according to the international relative atomic mass of 1989) Reference standards
Pictorial symbols for packaging, storage and transportation
GB 191
GB/T 601
GB/T 602
GB/T 603
GB 1250
Chemical reagentsPreparation of standard solutions for titration analysis (volume analysis)Preparation of standard solutions for impurity determination
Chemical reagents
Preparation of preparations and products used in chemical reagent test methodsExpression and determination methods of limit valuesGB/T 3049
GB/T 3051
GB 6003
General method for determination of iron content in chemical products-Phenanthroline spectrophotometric method-Hg method
General method for determination of chloride content in inorganic chemical products-Test sieve
GB/T 6678
GB/T 6682
General rules for sampling of chemical products
Specifications and test methods for water used in analytical laboratoriesGB8946 Plastic woven bags
3 Technical requirements
Appearance: white light powder.
Industrial magnesium oxide shall meet the requirements of the following table:
%(m/m)
Magnesium oxide (calculated as MgO)
Calcium oxide (calculated as CaO)
Content of hydrochloric acid insoluble matter
Sulfate (calculated as S(0)4) content
Sieve residue (150μm test sieve)
Approved as a superior product by the Ministry of Chemical Industry of the People's Republic of China on February 9, 1994
Implementation on July 1, 1994
Iron (Fe) content
Manganese (Mn) content
Nitride (calculated as CI) content
Loss on ignition
Bulk density.g/ml.
Test method
HG/T 2573--94
Superior
%(m/m)
The reagents and water used in this standard, unless otherwise specified, refer to analytically pure reagents and grade 3 water specified in GB/T6682. The standard titration solutions, impurity standard solutions, preparations and products required in the test, unless otherwise specified, are prepared in accordance with the provisions of GB/T601, GB/T602 and GB/T603. 4.1 Determination of wall content of magnesium oxide
4.1.1 Summary of the method
A small amount of trivalent iron, trivalent aluminum and divalent manganese ions are masked with monoethanolamine. At a pH of 10, chrome black T is used as an indicator, and the calcium and magnesium contents are titrated with disodium ethylenediaminetetraacetic acid standard titration solution. The calcium content is subtracted from the titration solution to calculate the magnesium oxide content. 4.1.2 Reagents and materials
4.1.2.1 Hydrochloric acid (GB/T622) solution: 1+1; Ethanolamine solution: 1+3;
4.1.2.3 Ammonia (GB/T631)-ammonium chloride (GB/T658) buffer solution A: pH~10; 4.1.2.4 Silver nitrate (GB/T670) solution: 10g/L; Disodium ethylenediaminetetraacetic acid (GB/T1401) standard titration solution: c(EDTA) is about 0.02mol/I; 4.1.2.5
4.1.2.6 Eriochrome black T solid indicator: 1% (m/m). 4.1.3 Analysis steps
4.1.3.1 Preparation of test solution
Weigh about 5g of sample (accurate to 0.0002g), place in a 250mL beaker, moisten with a small amount of water, cover with a watch glass, add hydrochloric acid solution (about 42ml.) to dissolve the sample, boil for 3~~5min, filter with medium-speed quantitative filter paper while hot, and wash with hot water until there is no chloride ion (check with silver nitrate solution). After cooling, transfer the filtrate and washing solution into a 500mL volumetric flask, add water to the scale, shake well, and obtain test solution A. Test solution A is used for the determination of magnesium oxide, calcium oxide, iron and sulfate content. Keep the residue and filter paper for the determination of hydrochloric acid insoluble matter. 4.1.3.2 Determination
Pipette 25.00 ml of test solution A (4.1.3.1) into a 250 ml volumetric flask, add water to the mark, shake well, pipette 25.00 ml of the test solution into a 250 ml conical flask, add 50 ml of water, 5 ml of triethanolamine solution, 10 ml of buffer solution and 0.1 g of chrome black T indicator, and titrate with disodium ethylenediaminetetraacetic acid standard titration solution until the solution changes from purple-red to pure blue. 4.1.4 Expression of analytical results
Magnesium oxide (calculated as MgO) expressed as mass percentage X, calculated according to formula (1): V
cX0. 040 30
500×250
HG/T 2573---94
The actual concentration of disodium ethylenediaminetetraacetic acid standard titration solution, mol/-The volume of disodium ethylenediaminetetraacetic acid standard titration solution consumed in the titration, mL; The volume of disodium ethylenediaminetetraacetic acid standard titration solution consumed in the titration of calcium in Article 4.2, mL; The mass of the sample, g;
The mass of magnesium oxide expressed in grams equivalent to 1.00mL disodium ethylenediaminetetraacetic acid standard titration solution [c(EDTA)=1.000mol/1.
4.1.5 Allowable difference
The arithmetic mean of the parallel determination results shall be taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.2%. 4.2 Determination of calcium oxide content
4.2.1 Method summary
A small amount of trivalent iron, trivalent aluminum and divalent manganese ions shall be masked with triethanolamine. At a pH of 12.5, calcium carboxylate indicator shall be used as an indicator and calcium ions shall be titrated with disodium ethylenediaminetetraacetic acid standard titration solution. 4.2.2 Reagents and materials
4.2.2.1 Sodium chloride (GB/T1266);
Sodium hydroxide (GB/T629) solution: 100g/L4.2.2.3
Triethanolamine solution: 1+3;
Disodium ethylenediaminetetraacetic acid (GB/T1401) standard titration solution: c(EDTA) is about 0.02mol/L4.2.2.4
4.2.2.5 Calcium carboxylate indicator [1-(2-hydroxy-4-sulfonyl-1-azo)-2-hydroxy-3-naphthoic acid) solid indicator: 1% (m/m); Grind the calcium carboxylate indicator and sodium chloride in a mortar in a ratio of 1+99, and store in a wide-mouth bottle with a ground-mouth stopper. 4.2.3 Analysis steps
Pipette 50.00mL of test solution A (4.1.3.1) into a 250mL conical flask, add 30mL of water and 5mL of triethanolamine solution, and add sodium hydroxide solution dropwise while shaking. When the solution just becomes turbid, add 0.1g of calcium carboxylic acid indicator and continue to add sodium hydroxide solution dropwise until the test solution changes from blue to wine red, with an excess of 0.5mL. Titrate with disodium ethylenediaminetetraacetic acid standard titration solution until the solution changes from wine red to pure blue.
4.2.4 Expression of analytical results
Calcium oxide (calculated as CaO) X2 expressed as mass percentage is calculated according to formula (2): X =Va:cX0. 056 08 ×100
m×500
Wu Zhong-
The actual concentration of the standard titration solution of disodium ethylenediaminetetraacetic acid, mol/L; V2—the volume of the standard titration solution of disodium ethylenediaminetetraacetic acid consumed in the titration, mL, (2)
-the mass of the sample weighed in Section 4.1.3.1, g; m
0.05608—the mass of calcium oxide in grams equivalent to 1.00mL of the standard titration solution of disodium ethylenediaminetetraacetic acid c(EDTA)=1.000mol/L>.
4.2.5 Allowable difference
The arithmetic mean of the parallel determination results shall be taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.03%. 4.3 Determination of hydrochloric acid insoluble matter content
4.3.1 Analysis steps
Transfer the residue and filter paper retained in 4.1.3.1 into a porcelain crucible with constant weight, incinerate at 850-900℃ to constant weight after ashing. 4.3.2 Expression of analysis results
HG/T 2573-94
The hydrochloric acid insoluble matter content X expressed as a mass percentage is calculated according to formula (3): X;=m=mx100
-the mass of the empty space, g;;
where: m,--
m2-the mass of the crucible and the residue after calcination, g; the mass of the sample weighed in 4.1.3.1, g. m
4.3.3 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.02%. 4.4 Determination of sulfate content
4.4.1 Summary of the method
In a slightly acidic solution, sulfate ions are precipitated with barium chloride and turbidity is compared with a standard turbidimetric solution of barium sulfate. 4.4.2 Reagents and materials
4.4.2.1 Hydrochloric acid (GB/T622) solution: 1+5; 4.4.2.2 Nitrogen water (GB/T631) solution: 1+9; 4.4.2.3 Barium chloride (GB/T652) solution: 100g/L; 4.4.2.4 Sulfate standard solution: 1mL solution contains 0.1mgSO4. 4.4.3 Analysis steps
(3)
Pipette 10.0mlL test solution A (4.1.3.1) and 2mL sulfate standard solution, place them in 50mL colorimetric tubes, add water to each until about 20mL, adjust the solution to neutrality with nitrogen water or hydrochloric acid solution, and check with pH test paper. Add 1mL hydrochloric acid solution and 2mL barium chloride solution, add water to the scale, and shake the spoon. Place in a 4050℃ water bath and compare the turbidity after 10min. The turbidity of the test solution shall not be deeper than that of the standard turbidity solution.
4.5 Determination of sieve residue
4.5.1 Instruments and equipment
4.5.1.1 Test sieve (GB6003): R40/3 series 200mmX50mm/0.150mm; 4.5.1.2 Soft brush: bristle length is about 3cm, brush width is about 5cm. 4.5.2 Analysis steps
Weigh about 10g of sample (accurate to 0.01g), transfer it to the test sieve, brush the sample lightly with a soft brush to make the powder pass through, and finally, place a piece of black paper under the sieve and brush the sieve until no trace is left on the black paper. Transfer the sieve residue to a surface blood of known mass and weigh it (accurate to 0.000 2g).
4.5.3 Expression of analysis results
The content of sieve residue X expressed as mass percentage is calculated according to formula (4): m2-ml×100
Wherein: m———mass of surface blood, g; m2——mass of surface blood and sieve residue, g; m-—mass of sample, g.
4.5.4 Allowable difference
(4)
The arithmetic mean of the parallel determination results is taken as the determination result. The absolute difference of the parallel determination results: the superior product and the first-class product shall not exceed 0.005%, and the qualified product shall not exceed 0.02%.
4.6 Determination of iron content
4.6.1 Summary of method
Same as Article 2 of GB/T3049.
4.6.2 Reagents and materials
Same as Article 3 of GB/T3049.
4.6.3 Instruments and equipment
HG/T 2573—94
Spectrophotometer: with an absorption cell of 3 cm thickness. 4.6.4 Analysis steps
4.6.4.1 Drawing of working curve
According to Article 5.3 of GB/T3049, select an absorption cell of 3 cm thickness and the corresponding amount of iron standard solution to draw the working curve. 4.6.4.2 Determination
Use a pipette to transfer 10 mL of test solution A (4.1.3.1) and 1 mL of hydrochloric acid solution (reagent blank solution) into 100 ml volumetric flasks respectively. Add water to about 40mL each. The following operations are carried out in accordance with Article 5.4 of GB/T3049, starting from "adjusting the pH to about 2" with ammonia water or hydrochloric acid solution.
Subtract the absorbance of the reagent blank solution from the absorbance of the test solution, and find the corresponding iron mass from the working curve. 4.6.5 Expression of analytical results
The iron (Fe) content X expressed as mass percentage is calculated according to formula (5): Xs:
Where: ml——-the iron mass found from the working curve, mg; m
-the mass of the sample, g.
4.6.6 Allowable difference
Take parallel determination The arithmetic mean of the results is the determination result. The absolute difference between the parallel determination results shall not exceed 0.005%. 4.7 Determination of manganese content
(5)
4.7.1 Summary of the method
In a strong acidic medium in the presence of phosphoric acid, divalent manganese ions are oxidized to purple-red permanganate ions using periodate, and their absorbance is measured using a spectrophotometer at the maximum absorption wavelength (525nm). 4.7.2 Reagents and materials
4.7.2.1 Phosphoric acid (GB/T1282);
4.7.2.2 Potassium periodate (HG/T3-1158); 4.7.2.3 Nitric acid (GB/ T626) solution: 1+1, 4.7.2.4 Manganese standard solution: 1mL solution contains 0.01mgMn. Use a pipette to transfer 10mL of manganese standard solution prepared according to GB/T602 into a 100mL volumetric flask, dilute with water to the mark, and shake to hook. Prepare it when needed.
4.7.3 Instruments and equipment
Spectrophotometer: with an absorption cell with a thickness of 3cm. 4.7.4 Analysis steps
4.7.4.1 Drawing of working curve
Add 0.00 (reagent blank solution): 5.00, 10.00, 15.00, 20.0 in a series of 250mL beakers in sequence. 0. Add water to about 40mL of 25.00mL manganese standard solution, add 10mL phosphoric acid and 0.5g potassium periodate, heat and boil until the purple-red color of permanganate appears, and then boil slightly for 5 minutes. After cooling, transfer all the solution into a 100mL volumetric flask, add water to the scale, and shake well. At a wavelength of 525nm, use a 3cm absorption cell, use water as a reference, adjust the absorbance of the spectrophotometer to zero, and measure its absorbance. Subtract the absorbance of the reagent blank solution from the absorbance of each standard solution, and draw a working curve with the manganese mass as the horizontal coordinate and the corresponding absorbance as the vertical coordinate.
4.7.4.2 Determination
HG/T 2573-
Weigh about 5g (about 2g for first-class products) of the sample (accurate to 0.01g), place it in a 250mL tall beaker, moisten it with a small amount of water, add about 35mL (about 15mL for first-class products) of nitric acid to dissolve it, and at the same time, add 10ml of water to another beaker with the same volume of nitric acid solution as the dissolved sample as the reagent blank test solution.
Heat the test solution and the reagent blank test solution to boil, filter them with medium-speed qualitative filter paper while they are hot, wash them with 50ml of water 4 times, and collect the filtrate and washings in a 250ml beaker. The following operation is carried out according to 4.7.4.1 starting from "add 10 ml phosphoric acid". Subtract the absorbance of the reagent solution from the absorbance of the test solution and find the corresponding manganese mass from the working curve. 4.7.5 Expression of analysis results
The manganese content X expressed as mass percentage is calculated according to formula (6): m
X.=mx1000
Where: m—the mass of manganese found from the working curve, mg; m||tt ||The mass of the sample, g.
4.7.6 Allowable difference
(6)
Take the arithmetic mean of the parallel determination results as the determination result. The absolute difference of the parallel determination results: the superior product shall not exceed 0.0005%, and the first-class product shall not exceed 0.002%.
4.8 Determination of chloride content
4.8.1 Summary of the method
Same as Article 2 of GB/T3051.
4. 8.2 Reagents and materials
Same as Article 3 of GB/T3051.
4.8.3 Analysis steps
Weigh about 10g of sample (accurate to 0.01g), place in a 250mL beaker, add 150mL of water, cover the surface, heat and boil for 5~7min, cool to room temperature, transfer to a 250mL volumetric flask, add water to the scale, shake well. After standing for 30min, dry filter, discard the first 10mL of filtrate, transfer 5 0mL filtrate, put it in a 250mL conical flask, add 2-3 drops of bromophenol blue indicator solution, add 1+6 nitric acid solution until it turns yellow, add 2-3 drops in excess. Add 1ml. diphenylazocarbonyl hydrazide indicator solution, and titrate with 0.02mol/1. mercuric nitrate standard titration solution until the solution changes from yellow to purple-red.
At the same time, perform a blank test.
Collect the mercury-containing waste liquid after titration and treat it according to the provisions of Appendix D of GB/T3051. 4.8.4 Expression of analytical results
The fluoride content (in terms of CI) X expressed as a mass percentage is calculated according to formula (7): (VV.)c×0. 035 45×100
17. 73(VV.)c
Wherein: V---the volume of the standard titration solution of mercuric nitrate consumed in the titration, mL; V. ---the volume of the standard titration solution of mercuric nitrate consumed in the titration blank test, mL; -the actual concentration of the standard titration solution of mercuric nitrate, mol/L, (7)
m--the mass of the sample, g;
0.03545--the mass of chlorine in grams equivalent to 1.00mL of the standard titration solution of mercuric nitrate (cL1/2Hg(NO.)2·H,O】=1.000mol/L).
4.8.5 Allowable difference
The arithmetic mean of the parallel determination results shall be taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.005%. 208
4.9 Determination of loss on ignition
4.9.1 Summary of method
HG/T 2573-94
At 850~900℃, the hydrated basic magnesium carbonate in the sample loses water and releases carbon dioxide, converts into magnesium oxide, and loses free water at the same time. The loss on ignition is determined based on the reduced mass of the sample. 4.9.2 Analysis steps
Weigh about 1g of sample (accurate to 0.0002g), place it in a porcelain crucible with constant weight, and ignite it at 850~900℃ to constant weight. 4.9.3 Expression of analysis results
The ignition loss X expressed as a mass percentage is calculated according to formula (8): X.=
Mass of the crucible and the sample before ignition, g;
Wu Zhong: m,---
m2——Mass of the residue and the crucible after ignition, g; —Mass of the sample, g.
4.9.4 Allowable difference
The arithmetic mean of the parallel determination results is taken as the determination result. The absolute difference of the parallel determination results shall not exceed 0.05%. 4.10 Determination of bulk density
4.10.1 Instruments and equipment
(8)
Bulk density tester
As shown in the figure, the funnel is fixed on the bracket, and the measuring cylinder is located below the center line of the funnel, with a spacing of 30 mm. The material is organic glass. Figure 1 Bulk density tester
1 Hopper; 2--Baffle; 3--Stand; 4 Measuring cup 4.10.2 Analysis steps
Within 1 min, allow the sample that has passed the 250μm test sieve to freely leak into a measuring cylinder of known mass and volume through the funnel. The top of the cone of the sample should be higher than the wall of the base cylinder. Use a ruler to scrape off the higher part and weigh it (accurate to 0.1g). 4.10.3 Expression of analysis results
Bulk density X expressed as mass percentage. Calculate according to formula (9): X.
Where: m——mass of sample and measuring cylinder, g; m2—mass of measuring cylinder, g;
V volume of measuring cylinder, mL.
4.10.4 Tolerance
HG/T2573-94
Take the arithmetic mean of the parallel determination results as the determination result. The absolute difference of parallel determination results shall not exceed 0.02g/mL. 5 Inspection rules
5.1 Industrial magnesium oxide shall be inspected by the quality supervision and inspection department of the manufacturer in accordance with the provisions of this standard. The manufacturer shall ensure that all products leaving the factory meet the requirements of this standard. Each batch of products leaving the factory shall be accompanied by a quality certificate. The contents include: manufacturer name, factory address, product name, grade, net weight, batch number or production date, proof that the product quality meets this standard and the number of this standard. 5.2 The inspection results of industrial magnesium oxide shall meet the requirements of this standard within half a year from the date of leaving the factory. 5.3 The user has the right to accept the industrial magnesium oxide received in accordance with the provisions of this standard. 5.4 Each batch of products shall not exceed 2t.
5.5 Determine the number of sampling units in accordance with the provisions of Article 6.6 of GB/T6678. When sampling, insert the sampler vertically from the center of the packaging bag to 3/4 of the depth of the material layer to take a sample. After quickly mixing the sample, reduce it to about 500g according to the quartering method, and pack it in two clean and dry wide-mouth bottles with stoppers and seal them. Paste labels on the bottles, indicating: manufacturer name, product name, grade, batch number, sampling date and name of the sampler. One bottle is used for inspection and the other bottle is kept for three months for reference. 5.6 If one indicator of the inspection result does not meet the requirements of this standard, re-sampling should be carried out from twice the amount of packaging for verification. Even if only one indicator of the verification result does not meet the requirements of this standard, the entire batch of products cannot be accepted. 5.7 When the supply and demand parties have objections to the product quality, they shall be handled in accordance with the provisions of the "Product Quality Law of the People's Republic of China". 5.8 The rounded value comparison method specified in GB1250 shall be used to determine whether the inspection results meet the standards. 6 Marking, packaging, transportation, storage
6.1 The packaging bags of industrial magnesium oxide should have firm and clear markings, including: manufacturer name, factory address, product name, trademark, grade, net weight, batch number or production date, this standard number, and the "wet-afraid" mark specified in GB191. 6.2 Industrial magnesium oxide is packaged in double layers, with the inner packaging made of polyethylene plastic film bags, with the following specifications: 10kg packaging: 960~1050X520~~620mm; 15kg packaging: 1200×680mm; 20kg packaging: 1150×800mm; thickness: 0.4~~0.8mm. The outer packaging is made of plastic woven bags, with the following specifications: 10kg packaging: 860~1050×500～600mm; 15kg packaging: 1100×660mm; 20kg packaging: 1050×700mm. Its performance and test methods shall comply with the provisions of GB8946A. The net weight of each bag of this product is 10kg, 15kg or 20kg. 6.3 For industrial magnesium oxide packaging, the inner bag is tied with vinyl rope or other ropes of equivalent quality, or sealed with other equivalent methods; the outer bag is folded at a distance of not less than 30mm from the bag edge, and the mouth is sewn with vinyl thread or other thread of equivalent quality at a distance of not less than 15mm from the bag edge, with a stitch length of not less than 10mm, neat stitches, uniform stitch length, and no leaking or skipping. 6.4 Industrial magnesium oxide should be covered during transportation to prevent rain and moisture. 6.5 Industrial magnesium oxide should be stored in a cool and dry place to prevent rain and moisture. Additional remarks:
This standard is proposed by the Technical Supervision Department of the Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of the Tianjin Chemical Research Institute of the Ministry of Chemical Industry. This standard is drafted by the Tianjin Chemical Research Institute of the Ministry of Chemical Industry, Lianyungang Salt Chemical Plant, Shanghai Dunhuang Chemical Plant and Xingtai Magnesite Mine. The main drafters of this standard are Yao Jinjuan, Liu Youruo, Shi Zuyu, Ma Guochang and Liu Haorang. This standard adopts rOCT844-79 (91) "Technical Conditions for Industrial Handling and Burning Magnesium Oxide". From the date of implementation of this standard, the original National Standard of the People's Republic of China GB9004 "Industrial Magnesium Oxide" will be invalid.1 Instruments and equipment
(8)bzxz.net
Bulk density tester
As shown in the figure, the funnel is fixed on the bracket, and the measuring cylinder is located below the center line of the funnel, with a spacing of 30 mm. The material is plexiglass. Figure 1 Bulk density tester
1 Hopper; 2--Baffle; 3--Bracket; 4 Measuring cup 4.10.2 Analysis steps
Within 1 min, allow the sample that has passed the 250μm test sieve to freely leak through the funnel into a measuring cylinder of known mass and volume. The top of the cone of the sample should be higher than the wall of the base cylinder. Use a ruler to scrape off the higher part and weigh it (accurate to 0.1g). 4.10.3 Expression of analysis results
Bulk density X expressed as mass percentage. Calculate according to formula (9): X.
Where: m——mass of the sample and the measuring cylinder, g; m2—mass of the measuring cylinder, g;
V volume of the measuring cylinder, mL.
4.10.4 Allowable difference
HG/T2573-94
Take the arithmetic mean of the parallel determination results as the determination result. The absolute difference of the parallel determination results shall not exceed 0.02g/mL. 5 Inspection rules
5.1 Industrial magnesium oxide shall be inspected by the quality supervision and inspection department of the manufacturer in accordance with the provisions of this standard. The manufacturer shall ensure that all products leaving the factory meet the requirements of this standard. Each batch of products leaving the factory shall be accompanied by a quality certificate. The contents include: manufacturer name, factory address, product name, grade, net weight, batch number or production date, proof that the product quality meets this standard and the number of this standard. 5.2 The inspection results of industrial magnesium oxide shall meet the requirements of this standard within half a year from the date of leaving the factory. 5.3 The user has the right to accept the industrial magnesium oxide received in accordance with the provisions of this standard. 5.4 Each batch of products shall not exceed 2t.
5.5 Determine the number of sampling units in accordance with the provisions of Article 6.6 of GB/T6678. When sampling, insert the sampler vertically from the center of the packaging bag to 3/4 of the depth of the material layer to take samples. After the sampled samples are quickly mixed, they are divided into about 500g by quartering method and divided into two clean and dry wide-mouth bottles with stoppers and sealed. Labels are attached to the bottles, indicating: manufacturer name, product name, grade, batch number, sampling date and name of the sampler. One bottle is used for inspection and the other bottle is kept for three months for reference. 5.6 If one of the indicators in the inspection results does not meet the requirements of this standard, samples should be taken from twice the amount of packaging for verification. Even if only one indicator in the verification results does not meet the requirements of this standard, the entire batch of products cannot be accepted. 5.7 When the supply and demand parties have objections to the product quality, they shall be handled in accordance with the provisions of the "Product Quality Law of the People's Republic of China". 5.8 The rounded value comparison method specified in GB1250 shall be used to determine whether the test results meet the standard. 6 Marking, packaging, transportation, storage
6.1 The packaging bags of industrial magnesium oxide should have firm and clear markings, including: manufacturer name, factory address, product name, trademark, grade, net weight, batch number or production date, this standard number, and the "wet-afraid" mark specified in GB191. 6.2 The packaging of industrial magnesium oxide is double-layer packaging, and the inner packaging is a polyethylene plastic film bag with the following specifications: 10kg packaging: 960~1050X520~~620mm; 15kg packaging: 1200×680mm; 20kg packaging: 1150×800mm; thickness: 0.4~~0.8mm. The outer packaging is made of plastic woven bags with the following specifications: 10kg packaging: 860~1050×500~600mm; 15kg packaging: 1100×660mm; 20kg packaging: 1050×700mm. Its performance and inspection methods shall comply with the provisions of GB8946A. The net weight of each bag of this product is 10kg, 15kg or 20kg. 6.3 For industrial magnesium oxide packaging, the inner bag is tied with vinyl rope or other ropes of equivalent quality, or sealed with other equivalent methods; the outer bag is folded at a distance of not less than 30mm from the edge of the bag, and the edge is sewn with vinyl thread or other threads of equivalent quality at a distance of not less than 15mm from the edge of the bag, with a stitch length of not less than 10mm, neat stitches, uniform stitch length, and no leaking or skipping. 6.4 Industrial magnesium oxide should be covered during transportation to prevent rain and moisture. 6.5 Industrial magnesium oxide should be stored in a cool and dry place to prevent rain and moisture. Additional Notes:
This standard was proposed by the Technical Supervision Department of the Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of the Tianjin Chemical Research Institute of the Ministry of Chemical Industry. This standard was drafted by the Tianjin Chemical Research Institute of the Ministry of Chemical Industry, Lianyungang Salt Chemical Plant, Shanghai Dunhuang Chemical Plant and Xingtai Magnesite Mine. The main drafters of this standard are Yao Jinjuan, Liu Youruo, Shi Zuyu, Ma Guochang and Liu Haorang. This standard refers to rOCT844-79 (91) "Technical Conditions for Industrial Handling and Burning Magnesium Oxide". From the date of implementation of this standard, the original national standard of the People's Republic of China GB9004 "Industrial Magnesium Oxide" will be invalid. 2101 Instruments and equipment
(8)
Bulk density tester
As shown in the figure, the funnel is fixed on the bracket, and the measuring cylinder is located below the center line of the funnel, with a spacing of 30 mm. The material is plexiglass. Figure 1 Bulk density tester
1 Hopper; 2--Baffle; 3--Bracket; 4 Measuring cup 4.10.2 Analysis steps
Within 1 min, allow the sample that has passed the 250μm test sieve to freely leak through the funnel into a measuring cylinder of known mass and volume. The top of the cone of the sample should be higher than the wall of the base cylinder. Use a ruler to scrape off the higher part and weigh it (accurate to 0.1g). 4.10.3 Expression of analysis results
Bulk density X expressed as mass percentage. Calculate according to formula (9): X.
Where: m——mass of the sample and the measuring cylinder, g; m2—mass of the measuring cylinder, g;
V volume of the measuring cylinder, mL.
4.10.4 Allowable difference
HG/T2573-94
Take the arithmetic mean of the parallel determination results as the determination result. The absolute difference of the parallel determination results shall not exceed 0.02g/mL. 5 Inspection rules
5.1 Industrial magnesium oxide shall be inspected by the quality supervision and inspection department of the manufacturer in accordance with the provisions of this standard. The manufacturer shall ensure that all products leaving the factory meet the requirements of this standard. Each batch of products leaving the factory shall be accompanied by a quality certificate. The contents include: manufacturer name, factory address, product name, grade, net weight, batch number or production date, proof that the product quality meets this standard and the number of this standard. 5.2 The inspection results of industrial magnesium oxide shall meet the requirements of this standard within half a year from the date of leaving the factory. 5.3 The user has the right to accept the industrial magnesium oxide received in accordance with the provisions of this standard. 5.4 Each batch of products shall not exceed 2t.
5.5 Determine the number of sampling units in accordance with the provisions of Article 6.6 of GB/T6678. When sampling, insert the sampler vertically from the center of the packaging bag to 3/4 of the depth of the material layer to take samples. After the sampled samples are quickly mixed, they are divided into about 500g by quartering method and divided into two clean and dry wide-mouth bottles with stoppers and sealed. Labels are attached to the bottles, indicating: manufacturer name, product name, grade, batch number, sampling date and name of the sampler. One bottle is used for inspection and the other bottle is kept for three months for reference. 5.6 If one of the indicators in the inspection results does not meet the requirements of this standard, samples should be taken from twice the amount of packaging for verification. Even if only one indicator in the verification results does not meet the requirements of this standard, the entire batch of products cannot be accepted. 5.7 When the supply and demand parties have objections to the product quality, they shall be handled in accordance with the provisions of the "Product Quality Law of the People's Republic of China". 5.8 The rounded value comparison method specified in GB1250 shall be used to determine whether the test results meet the standard. 6 Marking, packaging, transportation, storage
6.1 The packaging bags of industrial magnesium oxide should have firm and clear markings, including: manufacturer name, factory address, product name, trademark, grade, net weight, batch number or production date, this standard number, and the "wet-afraid" mark specified in GB191. 6.2 The packaging of industrial magnesium oxide is double-layer packaging, and the inner packaging is a polyethylene plastic film bag with the following specifications: 10kg packaging: 960~1050X520~~620mm; 15kg packaging: 1200×680mm; 20kg packaging: 1150×800mm; thickness: 0.4~~0.8mm. The outer packaging is made of plastic woven bags with the following specifications: 10kg packaging: 860~1050×500~600mm; 15kg packaging: 1100×660mm; 20kg packaging: 1050×700mm. Its performance and inspection methods shall comply with the provisions of GB8946A. The net weight of each bag of this product is 10kg, 15kg or 20kg. 6.3 For industrial magnesium oxide packaging, the inner bag is tied with vinyl rope or other ropes of equivalent quality, or sealed with other equivalent methods; the outer bag is folded at a distance of not less than 30mm from the edge of the bag, and the edge is sewn with vinyl thread or other threads of equivalent quality at a distance of not less than 15mm from the edge of the bag, with a stitch length of not less than 10mm, neat stitches, uniform stitch length, and no leaking or skipping. 6.4 Industrial magnesium oxide should be covered during transportation to prevent rain and moisture. 6.5 Industrial magnesium oxide should be stored in a cool and dry place to prevent rain and moisture. Additional Notes:
This standard was proposed by the Technical Supervision Department of the Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of the Tianjin Chemical Research Institute of the Ministry of Chemical Industry. This standard was drafted by the Tianjin Chemical Research Institute of the Ministry of Chemical Industry, Lianyungang Salt Chemical Plant, Shanghai Dunhuang Chemical Plant and Xingtai Magnesite Mine. The main drafters of this standard are Yao Jinjuan, Liu Youruo, Shi Zuyu, Ma Guochang and Liu Haorang. This standard refers to rOCT844-79 (91) "Technical Conditions for Industrial Handling and Burning Magnesium Oxide". From the date of implementation of this standard, the original national standard of the People's Republic of China GB9004 "Industrial Magnesium Oxide" will be invalid. 2105 Industrial magnesium oxide should be stored in a cool, dry place to prevent rain and moisture. Additional notes:
This standard was proposed by the Technical Supervision Department of the Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of the Tianjin Chemical Research Institute of the Ministry of Chemical Industry. This standard was drafted by the Tianjin Chemical Research Institute of the Ministry of Chemical Industry, Lianyungang Salt Chemical Plant, Shanghai Dunhuang Chemical Plant and Xingtai Magnesite Mine. The main drafters of this standard are Yao Jinjuan, Liu Youruo, Shi Zuyu, Ma Guochang and Liu Haorang. This standard refers to rOCT844-79 (91) "Technical Conditions for Industrial Handling and Burning Magnesium Oxide". From the date of implementation of this standard, the original National Standard of the People's Republic of China GB9004 "Industrial Magnesium Oxide" will be invalid. 2105 Industrial magnesium oxide should be stored in a cool, dry place to prevent rain and moisture. Additional notes:
This standard was proposed by the Technical Supervision Department of the Ministry of Chemical Industry of the People's Republic of China. This standard is under the jurisdiction of the Tianjin Chemical Research Institute of the Ministry of Chemical Industry. This standard was drafted by the Tianjin Chemical Research Institute of the Ministry of Chemical Industry, Lianyungang Salt Chemical Plant, Shanghai Dunhuang Chemical Plant and Xingtai Magnesite Mine. The main drafters of this standard are Yao Jinjuan, Liu Youruo, Shi Zuyu, Ma Guochang and Liu Haorang. This standard refers to rOCT844-79 (91) "Technical Conditions for Industrial Handling and Burning Magnesium Oxide". From the date of implementation of this standard, the original National Standard of the People's Republic of China GB9004 "Industrial Magnesium Oxide" will be invalid. 210
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.